Improvement in the process of tanning



UNITED STATES THOMAS CHASE, or NEW- YORK, N. Y., ASSIGNOR To GEORGE n; nlonnnnsr PATENT .OFFICE.

IMPROVEMENT :IN THE PROCESS OFITANNINGJ Specification forming part of Letters'Patent No. 1,018, dated November-25, 1838.

To all whom it may concern;

Be it known that I, THOMAS GHAsE,of the city of New York, have invented an Improvement in the Process-of Tanning Hides and Skins, for which process Letters Patent of the United States were granted to George H. Richards, of the said city, dated the 16th day of December,in the year 1833, bywhich improve ment the process is much simplified, room is economized, and the efi'e'et is more certain and rapid; and I do hereby declare that the following is a full and exact description thereof Instead of employing two vats, as in the process described by the said George H. Richards, I perform the whole operation in one single air-tight vat, which I use in the following inanner: I make an air-tight vat, cistern, or case of sufficient strength to sustain the pressure of the atmosphere when the air is exhausted therefrom. Within this vat or cistern I suspend or lay the hides or skins in any convenient manner and completely cover'the same with the tanning-liquor. The top of the cistern is fixed and secured to the, body of the vat or box by means of screws, or otherwise, with the intervention of leather or other'suitable substance to render the same air-tight.

the air'in the pores of the skin opens them and gives a ready admission to the liquor or ooze,

which in consequence penetrates to theinterior of. theskimpervading its whole massaed tanning it perfectly throughout. I sometimes,

' g-ree of atmospheric pressure.

hing-liquor has completely penetrated the hides after having continued this state of exhaustion j for some hours, admit the atmosphere into the vat, so as to exert its pressure upon the surface of the liquid, allowing it to do so for a short period of time, that it may aid in forcing the liquid into the exhausted pores, after which I again work the air-pump and remove the pressure. As occasion may require, I- renew the liquor in the vat by withdrawing it by a pump or other meansand returning it to a reservoir of bark or other tanning substance,

from which reservoir it is again freshly supplied by a tube orother means to the tanning-- vat. I also have a'harometer or gage connect. ed with the vat, by which to ascertain the do- After the tanpart of'the apparatus, the whole being such;

as any competent workman can' constructwithout special directionsfrom me, such apparatus having been before known and used for various purposes, and not being of my invention.

What I claim as constituting my improvement is-- I I p r The application of the principle of exhaustion to tan-vats after the skins or hides havetheen suspended or laid therein and they have been covered with the tanning liquor, in the mam ner and for the purpose herein fully set forth.

THOMAS CHASE. [L. s.] Witnesses:

GILBERT GOLDING, J. R. LOWZANA. 

